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问题 单项选择题

在职业健康安全管理体系中，绩效测量和监视的目．的和意图是( )。

A．主动评价潜在的事故或紧急情况，识别应急响应需求

B．持续不断的对组织和职业健康安全绩效进行监测和测量，以保证体系的有效运行

C．制定应急准备和响应计划，以减少和预防可能引发的病症和突发事件造成的伤害

D．预防事故和事件及不符合情况的近一步发生

答案

参考答案：B

填空题

现有含FeCl2杂质的氯化铜晶体（CuCl2·2H2O），为制取纯净的CuCl2·2H2O，首先将其制成水溶液，然后按下图所示步骤进行提纯：

已知H2O2、KMnO4、NaClO、K2Cr2O7均具有强氧化性，要将溶液中的Cu2＋、Fe2＋、Fe3＋沉淀为氢氧化物，需溶液的pH分别为6.4、6.4、3.7。

请回答下列问题 [（1）~（2）小题填标号] ：

（1）本实验最适合的氧化剂X是__________

A．K2Cr2O7           B．NaClO            C．H2O2                  D．KMnO4

（2）物质Y不可以是___________

A．CuO             B．CuCl2             C．Cu（OH）2             D．CuCO3

（3）若Y为Cu(OH)2，写出除去Fe3＋的离子方程式：                            

（4）加入氧化剂的目的是_______________________________________。

（5）最后能不能直接蒸发结晶得到CuCl2·2H2O？__________（填“能”或“不能”）。如不能，应如何操作？（如能，此空不填）_______________________________。
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单项选择题

The blue of the sea is caused by the scattering of sunlight by tiny particles suspended in the water. Blue light, being of short wavelength, is scattered more efficiently than light of longer wavelengths. Although waters of the open ocean are commonly some shade of blue, green water is commonly seen near coasts, especially in tropical or subtropical regions. This is caused by yellow pigments being mixed with blue water. Phytoplankton are one source of the yellow pigment. Other microscopic plants may color the water brown or brownish-red. Near the shore, silt or sediment in suspension can give water a brownish hue. Outflow of large rivers can often be observed many miles offshore by the coloration of suspended soil particles.Marine phytoplankton (Greek for "plant wanderers") are microscopic single-celled plants that include diatoms, dinoflagellates, coccolithophorids, green algae, and blue-green algae, among others. The growth of these organisms, which photosynthesize light, depends on a delicate balance of nutrient enrichment via vertical mixing, which is often limited by the availability of nitrogen and light. Diatoms are one-celled plants with patterned glass coverings. Each glass, or silicon dioxide box, is ornamented with species-specific designs, pits, and perforations making them popular with microscopists and, more recently, electron scanning microscopists.

Phytoplankton are the source of which color pigment

A．Red.

B．Green.

C．Yellow.

D．Blue.
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